Yes, but it would be an equally dramatic step to leave their normal anti-spam system in place, but then specifically exempt a particular hashtag from filtering.

Yes, but it would be an equally dramatic step to leave their normal anti-spam system in place, but then specifically exempt a particular hashtag from filtering. But of course you're right; the core problem is that the filtering process itself is completely opaque and inscrutable. We just have to take Twitter's word that it doesn't introduce explicit or implicit biases.